TMS320F28377S: 高速采样DMA搬运问题

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Part Number: TMS320F28377S

目前项目使用28377s，需要采样10kHz的正弦波形，现在程序配置ADC为连续采样，DMA通过EPWM进行触发，EPWM频率为1M，程序配置如下

EPWM部分：

EPwm5Regs.TBPRD = 100;//p->PERIOD;
EPwm5Regs.TBPHS.bit.TBPHS = 0;
EPwm5Regs.TBCTR = 0x0000;

EPwm5Regs.TBCTL.bit.CTRMODE = TB_COUNT_UPDOWN;
EPwm5Regs.TBCTL.bit.PHSEN = TB_DISABLE;
EPwm5Regs.TBCTL.bit.PRDLD = TB_SHADOW;
EPwm5Regs.TBCTL.bit.SYNCOSEL =TB_SYNC_IN;
EPwm5Regs.TBCTL.bit.CLKDIV = 0;
EPwm5Regs.TBCTL.bit.HSPCLKDIV = 0;
EPwm5Regs.TBCTL.bit.FREE_SOFT = 0;
EPwm5Regs.TBCTL.bit.PHSDIR = 0;

EPwm5Regs.CMPCTL.bit.SHDWAMODE = CC_SHADOW;
EPwm5Regs.CMPCTL.bit.SHDWBMODE = CC_SHADOW;
EPwm5Regs.CMPCTL.bit.LOADAMODE = CC_CTR_ZERO_PRD;
EPwm5Regs.CMPCTL.bit.LOADBMODE = CC_CTR_ZERO_PRD;
EPwm5Regs.AQCTLA.bit.CAU = AQ_CLEAR;
EPwm5Regs.AQCTLA.bit.CAD = AQ_SET;
EPwm5Regs.AQCTLB.bit.CBU = AQ_SET;
EPwm5Regs.AQCTLB.bit.CBD = AQ_CLEAR;

EPwm5Regs.DBCTL.bit.OUT_MODE = DB_DISABLE;
EPwm5Regs.AQSFRC.bit.RLDCSF =0x3;
EPwm5Regs.AQSFRC.bit.ACTSFA=0x1;
EPwm5Regs.AQSFRC.bit.ACTSFB=0x1;

EPwm5Regs.AQCSFRC.bit.CSFA = 0;
EPwm5Regs.AQCSFRC.bit.CSFB = 0;

EPwm5Regs.ETSEL.bit.SOCASEL = 1;//周期中断2 下溢1
EPwm5Regs.ETSEL.bit.SOCAEN = 1;
EPwm5Regs.ETPS.bit.SOCAPRD = 1;
EPwm5Regs.ETCLR.bit.SOCA = 1;
EPwm5Regs.CMPA.bit.CMPA = 50;

AD采样部分：

AdcaRegs.ADCCTL2.all = 0; // Single-ended,12bit resolution, not divider
AdcaRegs.ADCCTL2.bit.PRESCALE = 2;//系统时钟2分频//0x6; // 系统时钟4分频--50M //待定
AdcSetMode(ADC_ADCA, ADC_RESOLUTION_12BIT, ADC_SIGNALMODE_SINGLE);
// AdcaRegs.ADCCTL1.bit.INTPULSEPOS = 1;
AdcaRegs.ADCCTL1.bit.ADCPWDNZ = 1;
AdcaRegs.ADCINTFLGCLR.all = 0xFFFF; // 清所有的中断标志位
AdcaRegs.ADCINTSEL1N2.bit.INT1E = 1; // 禁止连续模式，禁止中断
AdcaRegs.ADCINTSEL1N2.bit.INT1CONT =1;
AdcaRegs.ADCINTSEL1N2.bit.INT1SEL =7;
AdcaRegs.ADCINTSOCSEL1.bit.SOC7 = 1;

AdcaRegs.ADCSOC7CTL.bit.CHSEL = 15; //ADCIN15

AdcaRegs.ADCSOC7CTL.bit.TRIGSEL = 0x0; // 软件触发模式

AdcaRegs.ADCSOC7CTL.bit.ACQPS = 14;

DMA部分：

DMAInitialize();
DMADest = (volatile Uint16 *)rdata;
DMADest2 = (volatile Uint16 *)rdata2;
DMADest3 = (volatile Uint16 *)rdata3;
DMADest4 = (volatile Uint16 *)rdata4;
//
// configure DMA CH1
//
DMACH1AddrConfig(DMADest, (uint16_t *)ADCARESULT_BASE+7);
DMACH1BurstConfig(1,0,1);
DMACH1TransferConfig(1000,0,1);
// DMACH1WrapConfig(0,0,0,1);
DMACH1ModeConfig(DMA_EPWM5A,PERINT_ENABLE,ONESHOT_DISABLE,CONT_DISABLE,SYNC_DISABLE,SYNC_SRC,OVRFLOW_DISABLE,SIXTEEN_BIT,CHINT_END,CHINT_ENABLE);

目前DMA搬运完触发中断后，在DMA中断中停止DMA搬运并处理搬运数组，处理完后打开DMA搬运，经过测试，采样5kHz波形时勉强够用，搬运出的数组幅值基本无衰减，波形存在少量锯齿，如下图所示